Certified Ophthalmic Assistant Practice Exam

Which imaging technique does not produce a color-coded map?

1. Fluorescein angiography

2. Indocyanine green chorioangiography

3. Optical coherence tomography

4. Fundus photography

The correct answer is: Indocyanine green chorioangiography

Indocyanine green chorioangiography primarily relies on infrared light to visualize the choroidal circulation and does not typically produce a color-coded map. This technique involves injecting indocyanine green dye, which fluoresces in the infrared spectrum, allowing for detailed imaging of blood flow in the choroidal layers of the eye. The images obtained are often greyscale or monochrome rather than color-coded, focusing on the structural and functional aspects of choroidal circulation without providing a comparative color visualization of different tissues or flows. In contrast, fluorescein angiography and fundus photography use color-coded imaging to highlight various structures of the retina and choroid. These techniques utilize the properties of fluorescein dye, which emits light in the visible spectrum after illumination, leading to colorful maps that detail blood flow and tissue condition. Optical coherence tomography can produce cross-sectional images that visualize retinal layers but does not typically present these in a color-coded map format like those derived from angiographic techniques.